Portable Multimode Persufflation/Perfusion System for Extended Hypothermic Kidney Preservation In 2011, over 110,000 patients in the US started treatment for end-stage renal disease (ESRD). These patients spend on average $70,000 annually on treatment, including dialysis. In The U.S. the current waiting list for organ transplantation holds over 100,000 patients in need of a new kidney and has been growing exponentially since 1989. Of those patients who do undergo successful organ transplantation are faced with further challenges of vitality, longevity, and cost. For example, transplanted organs last only 5-15 years on average, after which time the patient may need to be put back on the waiting list. It is widely recognized that organs exposed to short warm and/or extended cold ischemia do not perform as well as organs with less ischemic time. Minimizing ischemia and its effects are critical in improving organ outcomes. Currently methods of organ preservation are based on static cold storage (SCS), which are incapable of sufficiently oxygenating the organ. Oxygen has been shown to be the rate-limiting nutrient in stored tissue even under hypothermic storage. Gaseous perfusion (persufflation) provides humidified oxygen gas through the vasculature of the organ. Hypothermic humidified persufflation of organs has been demonstrated to better preserve and recondition a variety of organs and tissues such as heart, liver, pancreas, kidneys, and limbs. It has also been shown to enable the use of donated-after-cardiac-death (DCD) hearts, pancreases, livers, and kidneys in small and large animal experiments. Persufflation enables the maintenance of cellular energy stores (ATP) during cold storage; it also has been shown to preserve normal profiles of immunological and molecular markers, as opposed to control organs exposed to static cold storage that exhibit abnormal and damaging profiles especially upon rewarming. The overall goal of the technology is to improve organ quality for the same or longer storage time (particularly for DCD organs). This would contribute to more patients treated and better treatment outcomes. The objective of this Phase I STTR is to develop a kidney specific portable multimodal persufflation/perfusion system that can switch between gas persufflation and liquid perfusion. The system will be used in the development of new extended organ preservation protocols and advanced organ quality assessment measurements using porcine kidneys as a model. The multimodal kidney persufflation/perfusion system will enable the use of one system for complete enhanced kidney preservation and assessment.